The present invention relates to an actuator for actuating a bypass valve disposed in a bypass passage provided in an air intake tubine for changing the tuning point in an inertia supercharger for a multicylinder internal combustion engine.
Inertia supercharging for internal combustion engines utilizes a pressure wave generated upon closing of an intake valve in one engine cylinder to increase the charging efficiency for forcing intake air into orther engine cylinders. The inertia supercharging has heretofore been employed in many applications. Since the inertia supercharging relies on pressure waves for the inertia effect, it is most effective at a certain engine RPM which is known as a tuning point, with the charging efficiency being poorer at other engine RPM than the tuning point. To avoid this difficulty, it is necessary to change the tuning point dependent on the engine RPM.